Electric switch for stop-motion devices on knitting machines



March 13, 1956 E. VOSSEN 2,738,387

ELECTRIC SWITCH FOR STOP-MOTION DEVICES ON KNITTING MACHINES Filed Dec. 4, 1952 I l l W 4 4- INVENTOR EDWARD l cssslv 48 BY E ATTORNEY United States Patent ELECTRIC SWITCH FOR STOP-MOTION DEVICES ON KNITTING MACHINES Edward Vossen, Lynbrook, N. Y., assignor to Stop- Motion Devices Corp., Brooklyn, N. Y.

Application December 4, 1952, Serial No. 323,987 1 Claim. (Cl. 200-61.]6)

This invention relates to an electric switch for stopmotion devices on knitting machines.

The principal object of this invention is the provision of a switch for a stop-motion device which is responsive to the take-up or receiving spindle of a knitting machine, and more particularly, to the knitted fabric roll which is wound thereon. When the roll of knitted fabric attains a predetermined diameter, a feeler arm or probe is thrust into engagement with the switch arm herein claimed to ground the knitting machine circuit and thereby to stop the machine.

It is important that the switch construction be physically strong and that the switch action be positive and virtually instantaneous. In operation, the switch arm is struck a severe blow each time the roll of knitted fabric attains the predetermined diameter. The blow changes the position of the movable contact member of the switch and this has the effect of instantaneously grounding the circuit.

The switch which is herein claimed possesses these features of constructional or structural strength and virtually instantaneous operation. It possesses the further feature of being easily re-set to operative (open) position when the knitting machine is once again ready to run. The very same arm which is struck to ground (close) the switch is actuated or moved to re-set the switch to its operative (open) position.

An important feature of this switch is its locating means for accurately setting the switch in open or operative position. This feature comprises the simple use of a springurged ball in one switch member and a socket in another switch member to receive said ball. There is a contact member in one of said switch members and an insulated station in the other switch member. When one of said switch members is moved relative to the other switch member in order to set the switch in open, operative position, the spring-urged ball will enter the socket and the contact member will thereby be automatically aligned with the insulating spot or station. This constitutes what may be described as a spring lock which resiliently holds the switch in open position. The tension of the spring is overcome when the probe or feeler which engages the roll of knitted fabric strikes the switch arm and thereby moves one of the switch members relative to the other switch member. The spring-urged ball is thereby dislodged from the socket and the contact member is thrust away from the insulated station, thereby grounding the same.

A preferred form of this invention is shown in the accompanying drawing in which:

Fig. 1 is a plan view of a switch made in accordance with this invention, showing a bracket which supports said switch on the frame of a knitting machine.

Fig. 2 is an enlarged section through said switch showing the spring-urged contact member mounted in a fixed part of the switch and an insulated member or member made of insulating material mounted in a movable part 2,738,387 Patented Mar. 13, 1956 of the switch for engagement with said spring-urged contact member.

Fig. 3 is another section through the same switch, showing a spring-urged ball in the fixed part of the switch and a socket formed in the movable part of the switch to receive said ball and thereby to hold the switch in open or operative position, said section being taken on the line 3-3 of Fig. 2.

Fig. 4 is a transverse section on the line 4-4 of Fig. 1, showing a face view of the movable part of the switch and thereby showing the insulated station and the ball receiving socket.

Bracket 10 has a cut-out 12 which receives a part of the frame of a knitting machine in the general vicinity of the take-up spindle on which the knitted fabric is wound. Set screws 14 secure said bracket to the frame. A rod 16 is adjustably supported by bracket 10. It extends through a hole 18 formed in said bracket and it is held in place therein by means of one or more set screws 20. When set screws 20 are loosened, rod 16 may be moved both axially and angularly in said hole 18 so that its position relative to the take-up roll of the knitting machine may be adjusted as desired or as required.

At one end of rod 16 is switch 22 herein claimed. This switch comprises a fixed housing 24 which carries the movable parts of the switch and a movable housing 26 which carries the actuating means for operating the switch. More specifically, a hole 28 is formed in fixed housing 24 and said hole accommodates one of the ends of rod 16. One or more set screws 30 secure the fixed housing 24 to said rod. When set screws 30 are loosened, housing 24 may be moved both angularly and axially relative to rod 16 so as to change its position relative to said rod or for the purpose of either removing it from the rod or replacing it thereon. Set screws 30 will lock housing 24 in any desired or required position on rod 16. It will be apparent at this point, that the adjustment of rod 16 relative to bracket 10 is, in effect, an adjustment of switch housing 24 relative to said bracket and consequently relative to the frame of the knitting machine.

Switch housing 24 may be cylindrical in shape and this is also true of movable switch housing 26. A hole 32 is formed axially of movable housing 26 and a screw 34 in said hole engages fixed switch housing 24 to hold the two housings together. It will be noted that screw 34projects axially into housing 24 and that it is provided with a shoulder 36 which limits the inward movement of said screw into said housing 24. Consequently, although screw 34 may be tightened against housing 24, enough clearance will be left between its head and shoulder 38 of housing 26 against which it bears to permit of angular movement of said housing 26 relative to housing 24.

A transverse hole 40 is formed 26 to accommodate a rod 42. A set screw 44 secures said rod to said housing. It will be understood, that when screw 44 is loosened in housing 26, it will be possible to shift said rod 42 axially of itself so as to adjust its position relative to movable housing 26. It may also be turned about its own axis relative to housing 26 but this feature would have significance only in the event that rod 42 is not simply a straight rod but is provided at one end with a laterally bent or offset portion. It is this rod 42 which is struck to actuate the switch when the knitted fabric on the take-up spindle reaches a predetermined diameter.

A view of face 46 of housing 26, that is, of its surface which bears against housing 24, discloses that a recess or socket 48 is formed therein and further that an insulating plug 50 is inserted therein. This plug may simply be a cylindrical element made of electrically in movable housing insulating material,, such as Pl st cs. nud rubber or th like. This plug 50 constitutes the open station for the contact member of the switch. Recess or socket 48 is the negative or passive; element of" the. locking means which holds the switch in open position. Two longitudinally extendi'ngholes 52 and 54 respec tively are formed in fixed housing 24.. In one of these holes, namely 52, isse springrurged contact plunger 56 andrin, theothe-r hole, namely 5.4., is av spring-urged ball 58; Ball 53. is engageable' with socketeit so. as to lock housing 26 in a fixed angular position relative to housing A spring 69 urges said hall 5.8. in the, direction of housing. .26 and consequently when. housing. 26 is turned to the: point where. its socket .48 registers; with hole '4, ball 53 will enter said socket and will resiliently resist any further angular movement of housing 26 relative to housing 2.4.. A. screw plug 62 in hole 54. holds spring; 60 in place, in said hole. It may be unscrewed to remove said spring .and said. ball from; said hole.

Contact plunger 5.6 is: pointed. at its lower end sopas to limit. its. contact area. When housing: 26 is turned until hole 52 registers insulating plug 50:, said contact rod will engage said insulating plug with its pointed end so as to keep the circuit open. A. Spring; 64. in. hole 5.2 engages said contact rod 56 and urges it in the direction of housing 26., The action of spring 64 corresponds to that of spring 6-0. In addition, howeven. it serves. as a conductor for electrically connecting contact: plunger 56 with binding post or terminal 66.

This binding post or terminal is mounted in. a threaded plug 6.8 which. is made of insulating material such as plastics or hard rubber or fiber or the like... The. threaded plug is screwed into hole 52 or ity is otherwise; secured therein. It thereby serves to. hold spring 64 in place addition to insulating. binding post 66 from housing 24. Spring 64 is, of. course, in engagement. with binding post. 6.6 to electrically link said binding post, to contact plunger 56.

It will be understood that in the preferred iorm of this invention housings 24 and 2,6 are made of; metal, such as steel, for structural strength. Such being the case, it is necessary to insulate. spring 64- and contact. plunger 56. from the wall, of hole 52.. This is done by means of an insulating sleeve 70 which is interposed between said spring and contact rod on the one hand. and the wall of hole 52 on the. other hand. This insulating sleeve may be a plastic tube or a tube. made of hard rubber or fiber or the like.

It. will be. understood. that holes.- 52, and .54.-

situated in, the. fixed: switch housing. 24 for simultaneous. registration with. insulating element 50 and socket 48. when switch housing 26 is, in a given angular position relative to housing 24. Consequently, the spring-urged ball engages socket 48 to. retain the two housings said relative positions and to maintain the contact: member 56 in engagement with insulating element 5.0., The switch Vii is ne open- When rod 2 is struck by the probe o feeler which engages the receiving roll of knitted fabric, or when it is struck by any other element or moved by any other element, the efiect is to turn housing 26 relative to housingf 24 and to unseat ball 58. This has the further efiect of disengaging contact member 56 from insulating element 50 and thereby grounding said contactv member against face 46 of housing 26. The switch may be re-set by simply swinging rodv 42 back to its original position, which of course returns housing 26 to its original position relative. to housing 24 and thereby enables spring-urged ball 58' to re-seat itself in socket 43 and contactv member 56 to resume engagement with insulating element 59.

The foregoing is illustrative of a preferred form of this invention and it will be understood that this form may be modified and other preferred forms may be had within the broad spirit of the invention.

I claim:

An electric switch comprising a bracket, a rod adjustably supported by said bracket, 2. housing secured to saidv rod, a second housing secured to said first housing for angular movement relative thereto, an. actuating rod adjustably secured to said second housing, a pair of. holes formed in the first housing, a spring-urged contactmemher in one. of said holes, a binding. post connectedto said spring-urged contact member, an insulated element on the second housing which is engageable with. the springurged contact member when the secondv housing is in a predetermined angular position. relative to the first housing, a spring-urged ball in the second hole of first housing, and a socket for said ball iormed inthe second housing, said socket being in registration with. the second hole to receive said ball. when the second housing is in predetermined angular position relative to the first housing, thereby resiliently locking said second housing in said predetermined angular position relative to the first housing, an insulating sleeve being provided. in the first. mentioned hole formed in. the firsthousing, the springrurged contact member being slidably mounted within said sleeve, and an insulating bushing mounted in said first. mentioned hole. adjacent said insulating sleeve and supporting said binding post, whereby said spring urged contact member and said binding post. are. insulated from engagement with said first housing.

References Cited in the file of this. patent NI-TE TAT S PA EN 1,100,949 Briggs June 23,1914

1,581,735 Hart Apr. 20, 1926 2,542,708 Rogow Feb. 20, 1951 2,640,119: Bradford May' 26,, 1953 FOREIGN PATENTS 2.2.384- Norway Qct. 3.1; 1911 

